Mailscanner doesn’t like MS Office 2007 files because of the multiple extensions, treating it as a tricky archive. These files get quarantined, thus increasing your admin time. To resolve this problem:
Add a new line to filename.rules.conf (somewhere near the top)
allow \.xml\.rel$ - -
Make sure the 4 “words” are separated with tab characters and not spaces. This (along with its partner filetype.rules.conf) is the only place where tab characters must be used, as the regular expression matching the filename, and the reports (which are just “-” for an “allow” rule) could also contain spaces.
Solution from http://lists.mailscanner.info/pipermail/mailscanner/2007-September/078056.html
Check etc/Mailscanner/ directory for this file. Configserver installation, check /usr/mailscanner/etc.
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